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  • 1.
    A. Taher, Ali
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    BIM Software Capability and Interoperability Analysis: An analytical approach toward structural usage of BIM software (S-BIM)2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study focused on the structuralanalysis of BIM models. Different commercial software (Autodesk products and Rhinoceros)are presented through modelling and analysis of different structures with varying complexity,section properties, geometry, and material. Beside the commercial software, differentarchitectural and different tools for structural analysis are evaluated (dynamo, grasshopper,add-on tool, direct link, indirect link via IFC).

  • 2.
    Aagah, Orod
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Aryannejad, Siavash
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Dynamic analysis of soil-steel composite railway bridges: FE-modeling in Plaxis2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A soil-steel composite bridge is a structure comprised of corrugated steel plates, which are joined with bolted connections, enclosed in friction soil material on both sides and on the top. The surrounding friction soil material, or backfill, is applied in sequential steps, each step involving compaction of the soil, which is a necessity for the construction to accumulate the required bearing capacity. Soil-steel composite bridges are an attractive option as compared with other more customary bridge types, owing to the lower construction time and building cost involved. This is particularly true in cases where gaps in the form of minor watercourses, roads or railways must be bridged.

    The objective of this master thesis is the modelling of an existing soil-steel composite railway bridge in Märsta, Sweden with the finite element software Plaxis. A 3D model is created and calibrated for crown deflection against measurement data collected by the Division of Structural Engineering and Bridges of the Royal Institute of Technology (KTH) in Stockholm, Sweden.

    Once the 3D model is calibrated for deflection, two 2D models with different properties are created in much the same way. In model 1, the full axle load is used and the soil stiffness varied, and in model 2 the soil stiffness acquired in the 3D model is used and the external load varied. The results are compared to measurement data. In 2D model 1 an efficient width of 1,46 m for the soil stiffness is used in combination with the full axle load, and in 2D model 2 an efficient width of 2,85 m is used for the external load, in combination with the soil stiffness acquired in the 3D model.

    Aside from this, parametric studies are performed in order to analyse the effect of certain input parameters upon output results, and in order to analyse influence line lengths.

    Recreating the accelerations and stresses in the existing bridge using finite element models is complicated, and the results reflect this. Below are shown the discrepancies between model results and measurement data for the pipe crown. The scatter in the measurement data has not been taken into consideration for this; these specific numbers are valid only for one particular train passage.

    For crown deflection, the 3D model shows a discrepancy of 4%, 2D model 1 5% and 2D model 2 8% compared with measurement data. For crown acceleration, in the same order, the discrepancy with measurements is 1%, 71% and 21% for maximum acceleration, and 46%, 35% and 28% for minimum acceleration. For maximum crown tensile stress, the discrepancy is 95%, 263% and 13%. For maximum crown compressive stress, the discrepancy is 70%, 16% and 46%.

  • 3.
    Aagah, Orod
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Kardan, Caesar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Ett tillgängligt och användarvänligt boende: Anpassningsmöjligheter för människor med rörelsehinder och nedsatt rörelseförmåga2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this paper we have theoretically built a house designed for people with impaired mobility. The

    essay begins with an introduction in which the purpose of the work, the methodology and the

    depth-research part is presented. Then the layout that explains how we intend to adapt the house

    for the demands detailed in the depth-research part is presented. In the same chapter various

    structural components, such as different floors and walls, are specified.

    In the selection of materials we have taken into account the criteria of our specialization and

    adaptation to the aesthetic aspects, where we evaluate materials based upon our wishes regarding

    technique and form. There are also other aspects that are important in the selection of materials,

    including that these are adapted to technical traits of the construction elements and installations.

    In a later chapter the technical installations such as ventilation systems, heating systems,

    electricity and sanitation are presented, where both technical and financial aspects are described

    in detail. The economic aspects are also described in connection with calculating the building's

    power and energy requirements and then presented in the section where costs are accounted for.

    Finally, the work is summarized in the section “Conclusion and Discussion” in which we analyze

    all the work, and based on these analyses conclusions are drawn. During the course of work

    regulations such as Boverkets Byggregler (BBR) and other sources were used. These sources are

    presented in the bibliography section. We also received help and guidance from our supervisors

    in various parts of the work, which we are grateful for.

  • 4.
    Aalto, Jonatan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Neuman, Elisabeth
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Comparison of Punching Shear Design Provisions for Flat Slabs2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    A new generation of EN 1992-1-1 (2004) also known as Eurocode 2 is under development

    and currently there is a set of proposed provisions regarding section 6.4

    about punching shear, PT1prEN 1992-1-1(2017). It was of interest to compare the

    proposal with the current punching shear design provisions.

    The aim of this master thesis was to compare the punching shear resistance obtained

    in accordance with both design codes. Furthermore the eect of some parameters

    on the resistance was to be compared. It was also of interest to evaluate the userfriendliness

    of the proposal.

    In order to meet the aim, a case study of a real  at slab with drop panels was performed

    together with a parametric study of a pure ctive  at slab. The parametric

    study was performed for inner, edge and corner columns in the cases prestressed,

    without and with shear reinforcement.

    It was concluded that the distance

    av from the column axis to the contra  exural

    location has a big in uence on the punching shear resistance. The factor

    ddg

    considering concrete type and aggregate properties also has a big impact on the resistance.

    The simplied estimation of

    av according to 6.4.3(2) in PT1prEN 1992-1-1

    (2017) may be inaccurate in some cases.

    The length

    b0 of the control perimeter has a larger eect on the resistance in EN

    1992-1-1 (2004) than in PT1prEN 1992-1-1 (2017).

    In PT1prEN 1992-1-1 (2017), studs located outside the second row has no impact

    on the resistance.

    The tensioning force in a prestressed  at slab has a larger in uence on the resistance

    in PT1prEN 1992-1-1 (2017) than in EN 1992-1-1 (2004). Furthermore,

    the reinforcement ratio is increased by the tendons, and thus aect the resistance in

    PT1prEN 1992-1-1 (2017).

    Clearer provisions for the denition of the support strip

    bs for corners and ends

    of walls are needed in PT1prEN 1992-1-1 (2017).

    It may be questionable if the reduction of the perimeter for a large supported area in

    accordance with 6.4.2(4) in PT1prEN 1992-1-1 (2017) underestimates the resistance

    v

    in some cases.

    Considering the work-load with PT1prEN 1992-1-1 (2017), more parameters are

    included. However, they may not require that much eort to obtain.

    Keywords: Punching shear, resistance, concrete,  at slab, design provisions, Eurocode

    2, case study, parametric study, shear reinforcement, prestressed

    vi

  • 5.
    Abbas, Qaalid
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hussein, Abdiwahab
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Studie om framtagning av montageplaner: En granskning av monteringsprocessen för prefabricerat byggande2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Dagens industrier anpassar numera sin tillverkning för att kunna massproducera och dra ner på personal och kostnader. Detta innebär ökad automatisering med större och kraftigare maskiner, utrustning och verktyg. För att garantera säkerheten på arbetsplatsen är det därför viktigt att rätt skyddsanordning och myndighetskrav följs och används. I byggbranschen ställer arbetsmiljöverket krav på branschföretagen gällande arbetsmiljö och särskilda underlag för produktionsarbetet. Denna studie undersöker montageplanen som används vid industriellt byggande som innebär användning av tunga, prefabricerade, element vid husbyggnad.

    Syftet är att studera hur en montageplan planeras, upprättas och implementeras. Studien utförs på uppdrag av In3prenör och omfattar 10 veckors arbete. Författarna har tillhandahållits information kring montageplanen för två projekt som studerats jämsides. Det ena, ett pågående projekt, är Allégården som är ett ROT-projekt av ett vård- och omsorgsboende och det andra, projekt Arlanda, är en nybyggnation av en servicebyggnad. Metoder som använts för att uppnå resultatet har varit en kombination av litteraturstudier, granskning av montageplaner, platsbesök och intervjuer.

    Resultatet visar på att otydliga riktlinjer kring vad som ska inkluderas i montageplanen är det största skälet till att det blir fel på arbetsplatsen. Det har även från intervjuerna påpekats att på grund av den tidspressade situationen och målbilden att undgå förseningar kan det ske misstag som kan få allvarliga konsekvenser. För att förbättra kvaliteten i montageplanerna måste riktlinjer från arbetsmiljöverket och boverket bli tydligare gällande montageplanens innehåll. Det är också viktigt att kritiska moment som kan medföra ökade risker framgår i montageplanen, vidare kan montörer utbildas för att öka deras riskmedvetenhet.

  • 6.
    Abbasi, Mazhar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Dawit Ghebreigziabher, Kibret
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Objektklassificerad modellering och effektivisering avmängduttag2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The lack of fluent communication in the building industry has caught people’s attention because of

    time-based costs appearing in 2D and 3D modelling and takeoffs. These costs emerge in construction

    when miscommunication takes place between professionals in different projects.

    A research study of the subject has revealed the reason behind the current days’ miscommunication

    issues. The study shows that although the professionals tend to have an efficient way of working, the

    result isn’t very beneficial for the next man. Therefore a conclusion of the issue creates a demand for a

    mutual language in modelling and better softwares for takeoffs.

    This report’s results, with regards to optimization of modeling, has brought to light the use for the

    objectclassificationsystem BIP. These BIP-codes are used for branding objects in models of which the

    branding consists of unique codes. The code of every individual object has the purpose of being

    recognized by every project member and remain the same throughout the project.

    The proposal for the optimization of takeoffs is a software called VICO Office. The software contains

    well-advised methods for the import of models and close to automated takeoffs of these models.

    In conclusion, the study implies that there is sufficient motive to question the old ways of working and

    that light should be shed on new approaches. Technology and the industry face a constant change and

    the efficiency of current methods are never far away.

  • 7.
    Abbasi, Mozaffer
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Analys och implementering av VSL-System i FEM-Design för kontroll av stabiliserande effekt: En undersökning i syfte att fastlägga effekten av VSL-kablar i FEM-Design för att utvärdera dess stabiliserande påverkan.2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 8.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials2012In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 284, p. 18-29Article in journal (Refereed)
    Abstract [en]

    The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.

  • 9.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A field test study of airborne wear particles from a running regional train2012In: IMechE, Part F: Journal of Rail and Rapid Transit, ISSN 0954-4097, Vol. 226, no 1, p. 95-109Article in journal (Refereed)
    Abstract [en]

    Inhalable airborne particles have inverse health affect. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up.

    Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280 nm, 350 nm, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 μm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. FESEM images captured particles sizing down to 50 nm. The ICP-MS results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.

     

  • 10.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wahlström, Jens
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A study of airborne wear particles generated from organic railway brake pads and brake discs2011In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 273, no 1, p. 93-99Article in journal (Refereed)
    Abstract [en]

    Brake pads on wheel-mounted disc brakes are often used in rail transport due to their good thermal properties and robustness. During braking, both the disc and the pads are worn. This wear process generates particles that may become airborne and thus affect human health. The long term purpose of ‘Airborne particles in Rail transport’ project is to gain knowledge on the wear mechanisms in order to find means of controlling the number and size distribution of airborne particles. In this regard, a series of full-scale field tests and laboratory tests with a pin-on-disc machine have been conducted. The morphology and the matter of particles, along with their size distribution and concentration, have been studied. The validity of results from the pin-on-disc simulation has been verified by the field test results. Results show an ultra-fine peak for particles with a diameter size around 100 nm in diameter, a dominant fine peak for particles with a size of around 350 nm in diameter, and a coarse peak with a size of 3-7 μm in diameter. Materials such as iron, copper, aluminium, chromium, cobalt, antimony, and zinc have been detected in the nano-sized particles.

  • 11.
    Abbasiverki, Roghayeh
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of underground concrete pipelines subjected to seismic high-frequency loads2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Buried pipelines are tubular structures that are used for transportation of important liquid materials and gas in order to provide safety for human life. During an earthquake, imposed loads from soil deformations on concrete pipelines may cause severe damages, possibly causing disturbance in vital systems, such as cooling of nuclear power facilities. The high level of safety has caused a demand for reliable seismic analyses, also for structures built in the regions that have not traditionally been considered as highly seismically active. The focus in this study is on areas with seismic and geological conditions corresponding to those in Sweden and Northern Europe. Earthquakes in Sweden for regions with hard rock dominated by high-frequency ground vibrations, Propagation of such high-frequency waves through the rock mass and soil medium affect underground structures such as pipelines.

    The aim of this project is investigating parameters that affect response of buried pipelines due to high-frequency seismic excitations. The main focus of the study is on reinforced concrete pipelines. Steel pipelines are also studied for comparison purposes. The effects of water mass, burial depth, soil layer thickness and non-uniform ground thickness caused by inclined bedrock are studied. The results are compared to those obtained for low-frequency earthquakes and the relationship between strong ground motion parameters and pipelines response is investigated. It is shown that, especially for high frequency earthquake excitations, non-uniform ground thickness due to inclined bedrock significantly increase stresses in the pipelines. For the conditions studied, it is clear that high-frequency seismic excitation is less likely to cause damage to buried concrete pipelines. However, the main conclusion is that seismic analysis is motivated also for pipelines in high-frequency earthquake areas since local variation in the ground conditions can have a significant effect on the safety.

  • 12.
    Abbasiverki, Roghayeh
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Initial study on seismic analyses of concrete and embankment dams in Sweden2017Report (Other academic)
  • 13.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of buried reinforced concrete pipelines subjected to seismic waves2014Conference paper (Refereed)
  • 14.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Seismic response of buried concrete pipelines subjected to highfrequency earthquakesIn: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529Article in journal (Refereed)
    Abstract [en]

    Buried pipelines are tubular structures that cross large areas with different geological conditions. During an earthquake, imposed loads from soil deformations on concrete pipelines may cause severe damages. In this study, the use of two-dimensional finite element models of pipelines and surrounding soil for simulation of seismic waves that propagate from the bedrock through the soil are demonstrated. The models describe both longitudinal and transverse cross-sections of pipelines and the soil-pipe interaction is modelled as a nonlinear behaviour. The effects of uniform ground with different burial depths, soil layer thickness, soil stiffness and bedrock geometry on the seismic response of reinforced concrete pipelines is studied. Two earthquakes, with high and low frequency contents, are employed for the dynamic analysis. The results show that there is a much smaller risk of damage from high-frequency earthquakes, but that there is a significant effect on the response due to possible irregular ground with inclined bedrock.

  • 15.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Malm, Richard
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of shallowly buried reinforced concrete pipelines subjected to earthquake loads2014In: Nordic Concrete Research, ISSN 0800-6377, no 51, p. 111-130Article in journal (Refereed)
    Abstract [en]

    Buried reinforced concrete pipelines are widelyused in e.g. water and wastewater systems. Failure of these infrastructures mayresult in drastic effects and recently they have been brought into focus asvital components in safety systems for nuclear power installations. The highlevel of safety has here lead to a demand for reliable earthquake risk analyses.In this paper, methods are compared and the use of seismic design loadsdemonstrated. FE analysis in 2D of soil-pipe interaction under seismic wavepropagation is performed. The performance of concrete pipes subjected toseismic waves with different frequency content is evaluated with respect todifferent soil condition but also water mass effect.

  • 16.
    Abbaszadeh Shahri, Abbas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering. Islamic Azad University.
    An Optimized Artificial Neural Network Structure to Predict Clay Sensitivity in a High Landslide Prone Area Using Piezocone Penetration Test (CPTu) Data: A Case Study in Southwest of Sweden2016In: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529, p. 1-14Article in journal (Refereed)
    Abstract [en]

    Application of artificial neural networks (ANN) in various aspects of geotechnical engineering problems such as site characterization due to have difficulty to solve or interrupt through conventional approaches has demonstrated some degree of success. In the current paper a developed and optimized five layer feed-forward back-propagation neural network with 4-4-4-3-1 topology, network error of 0.00201 and R2 = 0.941 under the conjugate gradient descent ANN training algorithm was introduce to predict the clay sensitivity parameter in a specified area in southwest of Sweden. The close relation of this parameter to occurred landslides in Sweden was the main reason why this study is focused on. For this purpose, the information of 70 piezocone penetration test (CPTu) points was used to model the variations of clay sensitivity and the influences of direct or indirect related parameters to CPTu has been taken into account and discussed in detail. Applied operation process to find the optimized ANN model using various training algorithms as well as different activation functions was the main advantage of this paper. The performance and feasibility of proposed optimized model has been examined and evaluated using various statistical and analytical criteria as well as regression analyses and then compared to in situ field tests and laboratory investigation results. The sensitivity analysis of this study showed that the depth and pore pressure are the two most and cone tip resistance is the least effective factor on prediction of clay sensitivity.

  • 17.
    Abbaszadeh Shahri, Abbas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics. College of Civil Engineering, Roudehen branch, Islamic Azad University, Tehran, Iran.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Johansson, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    CPT-SPT correlations using artificial neural network approach: A Case Study in Sweden2015In: The Electronic journal of geotechnical engineering, ISSN 1089-3032, E-ISSN 1089-3032, Vol. 20, no 28, p. 13439-13460Article in journal (Refereed)
    Abstract [en]

    The correlation between Standard and Cone Penetration Tests (SPT and CPT) as two of the most used in-situ geotechnical tests is of practical interest in engineering designs. In this paper, new SPT-CPT correlations for southwest of Sweden are proposed and developed using an artificial neural networks (ANNs) approach. The influences of soil type, depth, cone tip resistance, sleeve friction, friction ratio and porewater pressure on obtained correlations has been taken into account in optimized ANN models to represent more comprehensive and accurate correlation functions. Moreover, the effect of particle mean grain size and fine content were investigated and discussed using graph analyses. The validation of ANN based correlations were tested using several statistical criteria and then compared to existing correlations in literature to quantify the uncertainty of the correlations. Using the sensitivity analyses, the most and least effective factors on CPT-SPT predictions were recognized and discussed. The results indicate the ability of ANN as an attractive alternative method regarding to conventional statistical analyses to develop CPT-SPT relations.

  • 18.
    Abbaszadeh Shahri, Abbas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Johansson, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Updated relations for the uniaxial compressive strength of marlstones based on P-wave velocity and point load index test2016In: INNOVATIVE INFRASTRUCTURE SOLUTIONS, ISSN 2364-4176, Vol. 1, no 1, article id UNSP 17Article in journal (Refereed)
    Abstract [en]

    Although there are many proposed relations for different rock types to predict the uniaxial compressive strength (UCS) as a function of P-wave velocity (V-P) and point load index (Is), only a few of them are focused on marlstones. However, these studies have limitations in applicability since they are mainly based on local studies. In this paper, an attempt is therefore made to present updated relations for two previous proposed correlations for marlstones in Iran. The modification process is executed through multivariate regression analysis techniques using a provided comprehensive database for marlstones in Iran, including UCS, V-P and Is from publications and validated relevant sources comprising 119 datasets. The accuracy, appropriateness and applicability of the obtained modifications were tested by means of different statistical criteria and graph analyses. The conducted comparison between updated and previous proposed relations highlighted better applicability in the prediction of UCS using the updated correlations introduced in this study. However, the derived updated predictive models are dependent on rock types and test conditions, as they are in this study.

  • 19.
    Abbaszadeh Shahri, Abbas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Naderi, Shima
    Modified correlations to predict the shear wave velocity using piezocone penetration test data and geotechnical parameters: a case study in the southwest of Sweden2016In: INNOVATIVE INFRASTRUCTURE SOLUTIONS, ISSN 2364-4176, Vol. 1, no 1, article id UNSP 13Article in journal (Refereed)
    Abstract [en]

    Shear wave velocity (VS) is an important geotechnical characteristic for determining dynamic soil properties. When no direct measurements are available, V-S can be estimated based on correlations with common in situ tests, such as the piezocone penetration test (CPTu). In the current paper, three modified equations to predict the V-S of soft clays based on a comprehensive provided CPTu database and related geotechnical parameters for southwest of Sweden were presented. The performance of the obtained relations were examined and investigated by several statistical criteria as well as graph analyses. The best performance was observed by implementing of corrected cone tip resistance (q(t)) and pore pressure ratio (B-q) which directly can be found from CPTu data. The introduced modifications were developed and validated for available soft clays of the studied area in southwest of Sweden, and thus, their applicability for proper prediction in other areas with different characteristics should be controlled. However, the used method as a suitable tool can be employed to investigate.

  • 20.
    Abbaszadeh Shahri, Abbas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Spross, Johan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Johansson, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Kartering av skredbenägenhet medartificiell intelligens2018In: Bygg & teknik, ISSN 0281-658X, no 1Article in journal (Other academic)
  • 21.
    Abbaszadeh Shahri, Abbas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Spross, Johan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Johansson, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Storskalig kartering av skredbenägenhet i västra Götaland med artificiell intelligens2018Conference paper (Other academic)
  • 22.
    Abdali, Yasser
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Holm, Lovisa
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    En jämförelse mellan Tekla Structures och Civil 3D i krökta betongkonstruktioner2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Within the construction industry, there is a lot of discussion around BIM (Building InformationModelling). There is a need to move away from customized 2D-drawings and instead focus oninformative models which can be used throughout the whole cycle of construction. This developmenthas been ongoing within house construction, but this approach is harder to implement within thefacility sector.The difficulty in implementing a more BIM-oriented approach within construction is partly due tosoftware currently not being fully developed to create informative and reliable models of constructionswith complex geometries, such as bridges.Since Trafikverket, the largest construction developer within Sweden, has started to place a largerdemand on 3D there is a need for both technology and human resource to develop.The aim of this dissertation is to present a case study investigating the suitability of the software TeklaStructure and AutoCAD Civil 3D to perform a 3D-model of a double-curved bridge. The two pieces ofsoftware will be contrasted in a final comparison whereby both pros and cons will be presented.The study has made it clear that BIM is not just about creating an informative model, but it is alsoabout an approach which has the ability to completely change the construction sector to work morecollaboratively and effectively.The comparison between the two relevant software in this study shows that they both have strengthsand weaknesses and are suitable for our purpose. However, they differ in how detailed models theycan create and how well they have the ability to work with BIM to a greater extent.

  • 23.
    Abdinasser, Ahmed
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tabatabaei, Sara
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Samverkan av jord och ovanliggande struktur i FEM-program: En studie av nya jordmodeller I FE-programmet 3D- Structure2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    De senaste åren har det funnits olika företag som har tillverkat avancerade mjukvaror inom byggbranschen. En del av mjukvaror är avsedd att skapa 2D ritningar och 3D modeller. Med hjälp av dessa verktyg har ingenjörer och arkitekter snabbt och enkelt skapat ritningar och modeller för projektering av konstruktioner. Utvecklingen inom detta område kallas BIM. Byggnadsinformationsmodellering, BIM, stödjer design av en byggnad genom alla faser och möjliggör bättre konstruktions-, tillverknings- och inköpsaktiviteter.

    Andra mjukvaror är tilltänkt att förutse hur en struktur reagerar på verkliga laster, vibrationer, värme och andra fysiska effekter. För detta används finita elementmetod, där kommer strukturen analyseras i element för ett noggrannare resultat. En utveckling inom detta område har också skett. Företaget Strusoft AB utvecklar FE-verktyg för analys av struktur. Den senaste nyheten är modul för beräkning av samverkan mellan struktur, grundläggning och undergrunden i form av jord. Modulen kallas 3D-Soil och används enligt Strusoft för modellering och analys av geokonstruktioner.

    I denna rapport redovisas modellering av en struktur och underliggande jord med finit elementanalysprogrammet, FEM-Design som är försett med den nya modulen 3D-Soil för geotekniska beräkningar.

    Målet är att jämföra resultat för moment utifrån samverkanskrafter mellan jord och struktur i FEM-Design med ett annat FEM-program, Lusas. Till skillnad från FEM-Design appliceras jord- och vattentryck som utbredd last i Lusas.

    Resultaten visar att det finns signifikanta skillnader mellan resultaten från analysprogrammen och det finns begränsningar i modelleringsverktyget som behöver utvecklas vidare.

  • 24.
    Abdu, Mohammed
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ullén, Philip
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Dimensionerande vattenförbrukning och dess variationer2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden, 2010, approximately 907 million cubic meters of drinking water was withdrawn from municipalities. All of this water must be transported, which is done through water pipes. To dimension these it requires that we know how much water that is to be distributed and it varies among others depending on the time of the day, week and year that the withdrawals occur. In today’s approach of designing new water pipes, amongst other ways, we use typical examples of consumption variations during the day of a similar area. In addition, arbitrary and experiential values of ‘ratio of peak hour to average day’ and ‘ratio of peak hour to average hour’ are used.

    Unfortunately today’s way of dimensioning water pipes has not been ensured due to inadequate detailed data on consumption quantity. The main purpose of this study is to confirm or refute today’s way of dimensioning water pipes.

    To verify this we have with detailed data from Norrvatten been able to see consumption quantity on an hourly basis which helps us assess today’s dimensioning process. By measuring the flow into 13 municipalities and then comparing them against each other regarding population size, distribution over categories of users and more, we have been able to get different dimensioning factors.

    In this report we can conclude that there is a need to update the factors regarding ‘ratio of peak hour to average day’ and ‘ratio of peak hour to average hour’. In order to further study the dimensioning factors, a system must be developed that can measure the precise consumer flow for different consumer categories on a more detailed level.

  • 25.
    Abdulbaki, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Mammar Chaouche, Abdelah
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Användning av flygaska i vattenbyggnadsbetong 2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Engineering Concrete is used as a collective term for concrete structures related to the hydropower plants, dams and heavier plants. With great success, concrete has been used for a very long time for these types of structures. These constructions make high demands on the concrete quality and construction design as they are expected to have a lifetime of a hundred years or more.

     

    In casting such concrete is exposed to a temperature which can lead to cracking of the newly cast structure. Because the temperature rise is the primary cause of cracking, you can use various methods to reduce this. An effective way to reduce the temperature rise is to try to keep the cement content in the concrete as low as possible, because at the adiabatic conditions may say that the total temperature rise is directly proportional to the cement content in the concrete. An effective way to reduce the temperature rise is to use out some fly ash instead of cement. Fly ash is a powder mass obtained in the production of electricity and heat in coal-fired plants and cogeneration plants. Fly ash is a puzzolanic material which means that it reacts with calcium hydroxide and water, and can thus partially replace cement clinker.

     

    The purpose of this report is to provide a better understanding of how the fly ash affecting hydraulic concrete. By reading this report you will get at first a basic knowledge of what the concrete, hydraulic concrete and fly ash are. Furthermore, the section that dealt with the cracking of the hydraulic concrete, general knowledge followed out causes and remedies. A comparison has been made between a typical water building structural component, with and without fly ash. What has been compared are how the construction affected with and without fly ash on strength, resistance and the risk of cracking. Furthermore, the temperature dot calculations performed with the program HACON. The purpose of the calculations was to show how the different parameters with and without fly ash affects the risk of cracking of a typical hydraulic structures.

     

    The result of the temperature calculations show that you get a lower temperature development in a monolith cast with the fly ash and the construction cements compared to a monolith molded with construction cement without fly ash. With the reduced temperature development arose lower tensions in the flyashmonolith. In the survey carried out in this report, the results show that there is tension that exceeds the tensile strength of the monolith without fly ash and thereby bursting the structure. The monolith examined with fly ash as crackreducing action occurs tensile stresses which are lower than the tensile strength and thus does not crack structure. The results show that the cracking in a typical hydraulic structures can be reduced with fly ash.

  • 26.
    Abdulkadir, Hesho
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kostov, Andrey Petrov
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Studie om energibesparing på OKQ8 i Häggvik samt andra energieffektiviserade byggnader2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report begins with a brief description of some of the most common measures for energy savings in buildings with recess in the solar collectors and photovoltaic panels which lays a solid foundation for our study. Next comes the main part of the study consisting of detailed descriptions of three of the top streamlined Swedish buildings.

    The main purpose of this study is to investigate some of the energy efficiency improvements done on the OKQ8’s gasoline station in Häggvik with a calculate part. Part of the task is to calculate how many photovoltaic cell panels should be installed in order to cover the whole buildings energy need. After that have we calculated the payback time and profitability of some of the installations at the petrol station. We have also studied other energy optimized buildings and compared their specific energy need with that of OKQ8.

  • 27.
    Abdulkhalik, Lauko
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Samuelsson, Paula
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ekonomiska konsekvenser vid stambyten som berör skyddsrum: -en förtydligande studie av fyra typfall2018Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Det här examensarbetet behandlar stambyten som passerar skyddsrum.Skyddsrum användas som skyddsutrymme för människor vid behov under nödsituationer. Deflesta skyddsrummen byggdes under 1951-1974 och de är i behov av underhåll ochrenovering.På grund av strikta lagar blir alla renoveringar som berör skyddsrum väldigt kostsamma förfastighetsägare.Studien undersöker fyra typfall av renoveringar och reder ut lagar. Förhoppningsvis blir deanvändbart för fastighetsägare för att förstå kostnaderna kring stambyten som berörskyddsrum.

  • 28.
    Abdulla, Nardien
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Ali, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Ett modernare sätt att dimensionera: En jämförelse för Huvudstaprojektet, FEM-design eller handberäkning ?2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This theses has been conducted in collaboration with Peab where the students had Tomas Schäfer and Peter Jansson as supervisors.

    This report addresses how a specific secondary build up, located in Huvudsta Centrum, could had been designed differently. The original frame was designed with the old BKR construction rules. But at the construction start a new construction standard was applied, the Eurocode. Therefore, the house got decreased in weight to meet the stricter Eurocode requirements.

    The current frame was designed using manual methods, which were compared with the results from the same frame calculated with a computer programme, FEM-Design 3D Structure. The report is based on the know-how of how a designer should proceed to join the production model and the analytical model. This to be able to designed in a BIM environment.

    The difference in results, between the two methods, was about 50% reeducation in purchased steel and about 40% in design-engineer costs. We have estimated a total saving of 141000 SEK for Peab.

  • 29.
    Abdulrahman, Keiwan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Potrus, Fadi
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Numerical analysis and model updating of a steel-concrete composite bridge: Parametric study & Statistical evaluation2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the year 2006, only 10 years after the steel- concrete composite bridge, Vårby bridge was built, fatigue cracks were found during an inspection. To further investigate the reasons and the potential danger of the cracks, an investigation under the commission of the Swedish Transport Administration was issued in 2009. After the detection of fatigue cracks, several measurements were carried out in order to monitor the static behavior by the use of strain gauges at selected positions along the bridge. The measurements from the strain gauges monitoring the global behavior were then used to calibrate an finite element model.

     

    The present report is part of the research of understanding the behavior of steel-concrete composite bridges. Numerical analysis and model updating have been used in order to understand and determine how different parameters affects the strain range and the global behavior. The numerical analysis and parameter study were performed in the Finite Element software Abaqus and programming language Python. The outcome of the parameter study was then used to perform the model updating by the method of falsification in MATLAB.

     

    The results from the parameter study and the model updating showed that the measured strains could be reached with a wide range of parameter combinations. Even with unreasonable parameter values, the measured strains were obtained. To investigate the reason for this, a multiple linear regression analysis was performed which showed that the strain range is strongly correlated to the Young’s modulus of steel and concrete and also to the connector elasticity, which resembles the studs in the real bridge.

     

    Two different finite element models, with two completely different input parameter values, obtain the same strain range for the global behavior. It is therefore not certain to assume that a model is accurate and valid based on the fact that the predicted strain range from the finite element model is close to the measured strain range since the global behavior of a steel- concrete composite bridge can be modeled by many different sets of parameters.

  • 30.
    Abed El-Fattah Safi, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Design and Bridges.
    Bridge Life Cycle Cost Optimization: Analysis, Evaluation, & Implementation2009Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 31.
    Abed, Mohamad Samir
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hosseinzade, Azita
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Parameterstyrd projektering av broar: Koppling mellan Rhinoceros-Grasshopper och Tekla Structures2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    New methods for project designing in the building construction industry have been developed by introducing modern and powerful BIM tools. Several of today’s constructions are designed according to three-dimensional principles.Tekla Structures is a powerful BIM tool that is capable of managing both house and infrastructure constructions. Despite this, the program cannot handle bridges with a horizontal and vertical curvature efficiently. The designers must instead rely on several other applications to manage complex bridge constructions.In order to use the advantages of Tekla Structures, the software needs to be evolved or complimented by other third party softwares. This project aims to integrate new working technics and introduce a method based on parametric design in Tekla Structures. Such form of modeling enables the modification of parameters to a desired model for the user.A script is created through a visual programming extension that generates a parametric based bridge models. The bridge type in this project was designed, is an integral bridge.The project has proved that parametric based design is more effectively and a solution to manage bridges with horizontal and vertical curvature.

  • 32.
    Aboudi, U
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Altaie, K
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Solvärme i krypgrunder2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 33.
    Aboudi, Ula
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Altaie, Kenan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Solvärme för krypgrunder2008Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 34.
    Aboutalebi, Ghareman
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Optimering av fackverksstolpar med konisk eller parallell form2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 35.
    Abrahamsson, Nora
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Söderström, Fanny
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Påbyggnad av bostäder på tak i Stockholm City: En möjlighet för att göra Stockholm City till en funktionsblandad och mer levande stadsdel2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Stockholm City is currently well composed in the aspect of commercial and public service. A consequence to this is a desolated City during the late night. A requirement to accomplish a more living inner city is a satisfying combination of functions whereas people are in motion between the home, work and other social activities. The main function missing today in City is habitats. A problem with supplying more accommodations in City is however the limited asset of ground area due to exploitation.

    In this thesis research is made whether it is possible to transform City into a mixed-function and thereby urban living area. With reference to the limited asset of ground area aswell as the opportunity to preserve the existing qualities that occupy these areas, a research is conducted for the purpose of more residential buildings with the method of expansion of existing buildings.

    The result of this thesis is a proposition for residential buildings on roof tops in City and the requirements for such project are being analyzed. The additional building is added to a specific building and by its shaping reflects a good residential environment and a design appropriate to the surrounding built-up area. The proposal consists of a rooftop landscape with eight pairs of houses. To insert accommodations throughout expansion of existing buildings generally is applicable in City and therefore an adequate solution to the problem considering the problems in the area.

  • 36.
    Abramsson, Marcus
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Brygiewicz, Alexander
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Partnering - Kundnytta i fokus2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The literature and research is limited in the subject costumer value in partnering projects. This contributed to the interest to perform an empirical study on the topic. It has not been shown to be appropriate to implement this on a specific issue or problem, when the available information deals with the theory and applications of partnering, not customer value.

    Given the above problem this papers purpose is to describe how the various contractors and clients, associated with partnering activities in Sweden, experiencing the work and factors that maximize customer value in a partnering project.

    A qualitative method where six people were interviewed, related to partnering activities in Sweden. The interviews are semi-structured and adapted to each interviewee.

    The most important conclusions that answer the purpose are:

     Understand the customers business

     Choose a form of compensation based on founded trust and project type

     All parties combined knowledge provides the right conditions for the customer to make the right decision

     Lack of common well-developed digital tools

     Make decisions at the right time

     Reference Surfaces and own final checks instead third party inspector

  • 37.
    Abrigian, Mari
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Almqvist Gärtner, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Möjligheter och utmaningar med internationella inköp: En studie av internationella inköp2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry in Sweden today are facing a major challenge in building society and following the pace of population growth. Rising material prices are today a fact, and at the same time there is a lack of capacity at the Swedish suppliers as they are bound up in supplier agreements for the coming years. The largest construction companies in Sweden have been working strategically with international suppliers for a long time to increase their margins and to secure their material needs.

    BTH Bygg AB is today a company that builds, renovates and maintains real estate in Stockholm. The company has expanded in recent years and is committed to strong growth by 2020. Work on international purchasing has previously been limited to BTH Bygg, but this type of purchase is today seen as a necessity to continued growth and to be competitive in that part of Sweden where most is built.

    The purpose of this study is to analyze BTH Bygg's existing purchasing process to further develop and propose improvements with international procurement as a starting point.

    The study has been conducted with the help of interviews to get a complete picture of the issues of international purchasing. BTH Bygg AB has a strong organization with a lot of experience related to the subject area, and focus has been on compiling these in order to come up with suggestions and ideas on how to handle international purchases. Recommendations are focused on areas related to supplier assessment, communication, logistics and product selection.

  • 38.
    Acar, Yalda
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Jingstål, Pontus
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Influence of the Non-linear Effects in the Design of Viscous Dampers for Bridge Cables2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this master thesis the performance of external viscous dampers attached to cables in cable-stayed bridges have been studied. A comparison has been performed between a linear and a non-linear cable model. The comparison was carried out for two bridge cables, one from the Dubrovnik Bridge and the other from the Normandie Bridge. The performance of the dampers have been measured in terms of maximum achieved damping ratio and minimum amplitude of vibration.

    The analysis was performed using the finite element method. The damping ratio was measured using both the half-power bandwidth method and by calculating the loss factor. The half-power bandwidth method can only be applied to a linear system. Therefore, the loss factor was evaluated for the linear model and compared to the results obtained using the half-power bandwidth method. From the comparison, it was concluded that the damping ratio evaluated using the loss factor was similar to the results obtained when using the half-power bandwidth method. However, when calculating the loss factor, it was of great importance that the resonance frequency of the system was accurately determined. The loss factor was then calculated for the non-linear model and compared to the results obtained for the linear model. Since the loss factor measures the energy dissipated in a system, it could be utilised for the non-linear model. When computing the strain energy for the non-linear model an approximate method was used to take into consideration the strain energy caused by the static deformation of the cable.

    From the comparison between the linear and non-linear cable models, it was concluded that the optimal damper coefficients obtained by both models are not significantly different. However, there is an uncertainty in the results due to the fact that an approximate method was used when calculating the strain energy for the nonlinear model. It was also observed that a very accurate evaluation of the system’s resonance frequency was needed to calculate the loss factor. It was also observed that the variation in amplitude of vibration for varying damper coefficient was small for all modes of vibration for the Dubrovnik Bridge Cable as well as for the first mode of vibration for the Normandie Bridge Cable. The difference in the results between the two bridge cables needs to be investigated further in order to get a better understanding of the results.

  • 39.
    Acar, Yalda
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Jingstål, Pontus
    KTH, School of Architecture and the Built Environment (ABE).
    Influence of the Non-linear Effects in the Design of Viscous Dampers for Bridge Cables2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this master thesis the performance of external viscous dampers attached to cables in cable-stayed bridges have been studied. A comparison has been performed between a linear and a non-linear cable model. The comparison was carried out for two bridge cables, one from the Dubrovnik Bridge and the other from the Normandie Bridge. The performance of the dampers have been measured in terms of maximum achieved damping ratio and minimum amplitude of vibration.

    The analysis was performed using the finite element method. The damping ratio was measured using both the half-power bandwidth method and by calculating the loss factor. The half-power bandwidth method can only be applied to a linear system. Therefore, the loss factor was evaluated for the linear model and compared to the results obtained using the half-power bandwidth method. From the comparison, it was concluded that the damping ratio evaluated using the loss factor was similar to the results obtained when using the half-power bandwidth method. However, when calculating the loss factor, it was of great importance that the resonance frequency of the system was accurately determined. The loss factor was then calculated for the non-linear model and compared to the results obtained for the linear model. Since the loss factor measures the energy dissipated in a system, it could be utilised for the non-linear model. When computing the strain energy for the non-linear model an approximate method was used to take into consideration the strain energy caused by the static deformation of the cable.

    From the comparison between the linear and non-linear cable models, it was concluded that the optimal damper coefficients obtained by both models are not significantly different. However, there is an uncertainty in the results due to the fact that an approximate method was used when calculating the strain energy for the nonlinear model. It was also observed that a very accurate evaluation of the system’s resonance frequency was needed to calculate the loss factor. It was also observed that the variation in amplitude of vibration for varying damper coefficient was small for all modes of vibration for the Dubrovnik Bridge Cable as well as for the first mode of vibration for the Normandie Bridge Cable. The difference in the results between the two bridge cables needs to be investigated further in order to get a better understanding of the results.

  • 40.
    Acar, Yalda
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Skrobic, Karina
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Småhuset – val av bergvärme, fjärrvärme eller pellets2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the new construction of a small house and it includes studies of three heating systems: geothermal heating, district heating and pellet. The purpose of this thesis is to project a small house which can manage Building Regulations, BBR conditions and then examine three possible heating systems for the small house. This thesis is a literature study which gives an understanding of the heating systems technical structure, properties and costs. An empirical study completes the literature study by giving a deeper understanding of district heating costs and pellet costs. The empirical study contains two interviews, one of which was conducted in a district heating corporation and the other interview was conducted in a pellet corporation. The interview persons have answered structured questions in investment, maintenance and operating costs. The studies shows that the three heating system are different from each other for example the investment costs for district heating is much cheaper than the investments cost for pellets and geothermal heating. Finally, settles a comparison in the three heating systems properties and costs settles through a value analysis. The value analysis was an effective method when we based on literature studies and empirical studies made a valuation of the heating systems properties, investment costs, maintenance and operating costs. A weighting showed that district heating as heating system is the most optimal solution for the small house located in Borlänge.

  • 41.
    Aderskog, Mikael
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Hoff, Christopher
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Energi- och kostnadseffektiva klimatskal: För lager-, industri- och kontorsbyggnader2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A study to optimize insulation thickness for stock-, industrial- and office-buildings for external walls and roof in an economical perspective has been conducted on behalf of DynaMate. DynaMate’s role is to maintain all Scania’s buildings. Analysis has also included other parts of the building envelope, such as windows, exterior doors and industrial doors. In this thesis, three different types of exterior wall constructions has been investigated, these are a sandwich design consisting of sheet metal and a another one consisting of concrete, as well as a wall of concrete with a coating of plasters. Furthermore, two types of roof structures have been studied, these are TRP-sheets and a concrete structure, both of which are externally isolated. For all types of building envelopes, different standard thicknesses of insulation have been used and the U-value of the windows has been varied.

    To calculate the energy needed for the different kinds of buildings, the program IDA Indoor Climate and Energy has been used.  Furthermore, a sensitivity analysis of the air tightness has been implemented for the building envelope. Based on the program results LCC (Life-cycle cost) calculations have been carried out for all combinations, thus be able to form an idea of ​​the combination and what kind of structure that is most economically tenable.

    A thermograph study was conducted in an existing warehouse at Scania. Observations show that the connection between the sandwich material of sheet metal and the foundation wall is flawed as this has a much lower thermal resistance compared to other parts of the building envelope. An alternative connection was developed which reduces the heat loss to one-fifth of the initial connection.

    An analysis regarding the companies approach to the vapour barrier in roof structures for industrial buildings has been investigated from a moisture standpoint. The analysis shows that without a functioning vapour barrier the moisture content in the construction increases over time, which leads to increased heating costs.

    The conclusion of this study shows that a reduction of insulation thickness for all types of studied buildings is more economically tenable than increasing the thickness. This is mainly due to the high cost of capital that the company uses for these investments. This means that any savings on cooling and heating costs very quickly is overthrown by the interest rate of the additional cost of the investment.

  • 42.
    Aderskog, Mikael
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Jamil, Hilal
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Det fuktfria huset2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 43.
    Adevik Hammensten,, Sebastian
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Axelsson, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Solsidan – Utnyttjande av solenergi i småhus2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 44.
    Adevik, Sebastian
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Effekt av överlast på förstärkt jord: FEM- analys för att visa överlastens verkningsgrad på krypsättningar i kalkcementpelarförstärkt lös jord2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Applicering av överlast på kalkcementförstärkta jordar är ofta förekommande idag, forskning indikerar dock på att överlasten här, inte ger samma effekt som på oförstärkta jordar. Med grund i uppmätta värden i fält, visas i denna rapport, sättningsdifferenser mellan att använda överlast jämfört med att endast applicera brukslast. Resultat av analyserna visar på sättningsbeteende observerat i fält. Om erforderlig liggtid för brukslast finns, uppstår endast små sättningsdifferenser mellan att använda överlast eller inte.

    Genom att utföra sensitivitetsanalys i FEM- programvaran PLAXIS studeras kryputvecklingen i den förstärkta jorden. Effekten av att applicera en överlast visas för krypsättningar över lång tid.

    Inget resultat från de numeriska FEM- analyserna visade att märkbart gynnsam effekt uppstår på grund av överlastens applicering, med avseende på krypsättningar.

    De numeriska analyserna utförs i 2 och 3 dimensioner för att belysa effekt av förenkling av ett lastfall som inte uppfyller krav för oförstärkta jordar i plant töjningstillstånd.

    Utöver detta ges efter en litteraturstudie, förslag på hur vissa indataparametrar kan utvärderas från empiriska relationer. Indataparametrar som ligger till grund för analyserna är utvärderade från sonderingsresultat i kombination med värden från laborationsförsök och empiriska data.

  • 45.
    Adjamloo, Pedram
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Benjaro, Marc
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Renovering av miljonprogrammet: Ur ett ägarperspektiv2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Apartment buildings built between the years 1961-1975, also known as ”miljonprogrammet”, are in need of extensive renovations. The need for renovations stems from wear and tear, but it is also due to a lack of maintenance work. The renovations costs for these areas are often enormous. In addition to wear and tear, the need for renovations are due to the technical condition of the house, but also because of stricter governmental requirements, high energy consumption, social factors, higher demands and a need for modern apartments. The government has been clear with its intentions not to contribute financially to the renovations and improvements of miljonprogrammet. This means that decision makers in real estate companies will soon have to make a verdict concerning the need for renovations and make concrete decision on how the apartments are to be renovated. There are good opportunities for renovations of miljonprogrammet, but the opportunities are often limited by the property owners’ and the tenants’ economic capabilities, and building- and governmental requirements.

    This study will highlight what needs, opportunities, and limitations are put on owners and managers of properties when it comes to renovations of miljonprogrammet.

    Questions:

    • What controls the owner’s decision concerning possible renovations?
    • What controls the owner’s decision concerning extent of possible renovations?
    • What is the owner’s view on the different forms of contracts between owner and entrepreneur concerning procurement of renovations contracts?

    Open interviews with property owners have shown that property owners’ decisions concerning a possible renovation of miljonprogrammet are largely controlled by the properties technical condition. Prerequisites for renovation vary depending on property area and property market. This has significance in terms of opportunities for financing the need for renovation through raise in rent. Concerning the extent of renovations, the property owners want a reasonable economic cost with profit and returns in five to ten years. This is limited by governmental requirements, rules, and decisions that in certain cases can lead to the property owner being forced to reduce measures, demolish houses, sell the houses, or not put in an effort at all.

    It seems normal for property owners to choose a form of contract with regards to the resources and knowledge found in the company. When choosing a form of contract, the property owners prefer to contract out the totality of the renovations when it concerns larger properties because there are many unforeseen moments in a renovation contract. The property owners also want to split up the renovations in several stages to promote continued cooperation with entrepreneurs and to force the entrepreneurs to do their best to go on to later stages of the renovations. The forms of compensation considered to be most suitable are either fixed price or fixed price with incentive. It is considered important to incentivize or give a carrot to the entrepreneur for committed work. The choice of entrepreneur is controlled by several factors because of the complexity of renovating a property.

    Requirements put on entrepreneur:

    • Committed organization
    • Competent organization
    • References of similar projects
    • Economic strength
    • Experience of work with tenants
  • 46. Adler, J
    et al.
    Bergholm, Fredrik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Highway and Railway Engineering (closed 20110301).
    Pagakis, S
    Parmryd, I
    Noise and colocalization in fluorescence microscopy: solving a problem2008In: Microscopy and Microanalysis, ISSN 1431-9276, E-ISSN 1435-8115, Vol. 22, no 5Article in journal (Refereed)
  • 47.
    Adnan Alromi, Sandra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Singh Sidhu, Jivi
    Arbetsberedning som verktyg för att förbättra arbetsmiljön2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To safely and effectively carry through within the construction industry, planning plays an important part. Work preparation is one form of planning. When using the model of work preparations, one analyzes the specific work preparation with the intent and goal to carry through the labor within the beforehand estimated time, budget and quality, while still maintaining satisfying work environment.The aim of this paper is to, from a perspective of work environment, map out how NCC: s work preparations function today. The goal is to provide suggestions for improvement. This can be done by performing interviews and surveys on the NCC employees.The results indicate that the staff of NCC see work preparation as a helping aid in improving work environment. However, there are also shortcomings in the way work preparations are done at NCC, and these could be improved. We therefore recommend NCC to make improvements in the planning, realization and the follow-up phase when setting up a work preparation. Our suggestions for improvement can be found under “recommendations”.

  • 48. Adolfi, Bengt
    et al.
    Hameury, Stephane
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Jegerfors, K
    Landström, A
    Trälyftet: Ett byggsystem i massivträ för flervåningshus2005Report (Other (popular science, discussion, etc.))
    Abstract [en]

    Trälyftet" presenterar ett byggsystem - bestående av industriellt tillverkade volymer med stommar av massivträ - som gör det möjligt att bygga moderna, robusta flervåningshus av prefabricerade volymer i massivträ. Vi får ta del av forskningen bakom byggsystemet, funktionen och erfarenheterna från det första prototyphuset. Även konstruktioner och installationer beskrivs.

  • 49.
    Adolfi, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Eriksson, Josefine
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Islastens inverkan på brottsannolikheten för glidning och stjälpning av betongdammar2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are many old dams in Sweden and, since few dams are constructed today, the main task in risk assessment on the existing dams is often to reduce the risk of failure. RIDAS (Swedish Guidelines on Dam Safety) is used when designing new dams and assess the existing ones. The guidelines include stability requirements for different failure modes, e.g. overturning and sliding, which imply that the load effect from e.g. uplift and ice load need to be less than the resisting loads or moments. The ice load in RIDAS is given as a deter­ministic value depending on where in Sweden the dam is located. For many years, ice and ice load have been researched, but there is still a lack of knowledge regarding the magni­tude of the ice load and how it affects the probability of failure for dams. More knowledge about the actual ice load would result in a lower calculated probability of failure for the dam which could be used to design slender dams or avoid unnecessary reinforcement of existing dams.

    Dam safety evaluation is often performed with deterministic methods based on safety factors. In recent years, the use of probabilistic methods in dam design has increased. The method has an advantage compared to deterministic methods in safety evaluations of existing dams, since probabilistic methods provide an answer to which parameters that have the greatest impact on the stability of the dam and take into account the variations in each parameter.

    I this master thesis, a statistical distribution for the variation of the ice load’s annual maxi­mum value was calculated. This was used in the analysis of the probability of failure for solid gravity concrete dams and buttress concrete dams. The probability of failure was cal­culated for dams of different sizes for overturning and sliding failure modes, and also for three different load cases; without ice load, with a truncated ice load distribution and with an ice load distribution that has not been truncated. The probabilistic stability analysis was conducted in Comrel with ice load as one of the stochastic variables. It was found which sizes of the dams that have the largest impact from the ice load; also what effect extreme values on the ice load has on the failure probability of the dam.

    The results indicated that the probability of failure for dams lower than 15 m is more affected by the ice load, for both failure modes analyzed. The probability of failure is reduced for all dam types when eliminating extreme values of the ice load, particularly for dams lower than 15 m. In several cases, truncation of the ice load distribution is the differ­ence between an accepted and a non-accepted level of the probability of failure. It is also shown that reduced coefficient of variance for the ice load results in a decreased probability of failure. The conclusion is that solid gravity dams and buttress dams lower than 15 m, with a high consequence class, should be risk assessed with the ice load as a stochastic vari­able. The statistical distribution of the ice load is still uncertain and the distribution used in this report should not be used globally, rather in areas with a climate similar to northern Sweden. The reason for this is that the measurements that were used to derive the global distribution were mainly performed in areas with conditions similar to those in northern Sweden.

    A recommendation for further research is to focus on determining statistical distributions for the ice load for southern, central and northern Sweden. An alternative is to use differ­ent ice load distributions for the different areas. Another alternative could be to use the same statistical distribution for southern, central and northern Sweden but with different values for where the ice load distribution is truncated, depending on the maximal ice thick­ness in each area. The recommendation is also to develop a reliable method for measuring the ice load. In addition, attempts should be made to determine whether extreme values on the ice load really exist or if they are effects of measurement errors.

    Key words: concrete dams, ice load, probabilistic stability analysis, probability of failure

  • 50.
    Adolfsson, Hanna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Jansson, Johanna
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Miljonprogramhusens framtid ur energisynpunkt: Så ställer sig fastighetsägarna till omfattande renoveringar2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Climate change in the world is a fact and to stop the effects that the greenhouse gas emissions causes requires the society to take action. The construction industry is a major cause of this and has led the government to establish energy requirements with the goal to reduce the carbon footprint. The large number of multi-apartment dwellings, the so called Million Homes Programme, built in 1965-74 causes severe environmental impact hence them aging at the same time.  

     

    The aim of this thesis is to, from an energy perspective, investigate how property owners of the Million Homes Programme will act on future renovations. A preliminary research of relevant literature was implemented to gain a better understanding in the chosen subject and appropriate material to perform the interviews. 

     

    All of the interviewed property owners are working on getting their houses more energy efficient and believe they have a good economy to carry through. However, the choice of action is based on the buildings condition and the required rate of return that the property owners are after. Further they are looking to achieve the goal of reducing their energy use by 20 percent by 2020 for their overall housing stock but not specifically for their Million Homes Programme. Great demands are made on the majority of the property owners to do more energy efficient renovations in order to reach the aim of a 50 percent energy use reduction by 2050.

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